Optimal control of quantum discord in a common environment

We get the dynamical evolution of quantum correlation for the general Werner state immersed in a common Ohmic bath. The optimal control can be derived using Pontryagin maximum principle. It is found that the control field obtained is helpful to suppress the environmental noises, in the sense of slowing down the decay of discord and prolonging its available existing time. Our numerical work demonstrates that the controlled discord can effectively exist almost eighth as long as the one without control.